The present invention relates generally to a foldable portable phone (which includes a personal digital cellular (“PDC”) and a personal handy phone system (“PHS”)), and another mobile communication terminal, which are generically referred to as “mobile radio communication apparatus” in the instant application, and more particularly to an internal structure of its hinge part.
Recent widespread mobile radio communication apparatuses, such as PDCs, have roused various demands including operational comfortableness and safety, apparatus's versatility and smaller housing, etc. in addition to mere communications.
In general, there are two types of portable phones, i.e., foldable portable phones and non-foldable, rod-shaped portable phones. The foldable portable phones typically include a movable part that contains a liquid crystal display (“LCD”) screen, a fixed part that contains a ten-key, and a hinge part that connects them foldably. Some foldable portable phones include a free stop function, a one touch opening function, and a safety-improving oil damper (see, for example, Japanese Patent Applications Publications Nos. 2002-344597, 2002-364629, 2002-139020, 10-51526, 9-130462, 8-331219, 8-186629, 6-268724, and 5-336022, and Japanese Utility-Model Registration No. 3,088,332). For the apparatus's versatility, the camera function and Internet access function that allows a user to access the Internet to download Web information and motion-picture information.
The free stop function is one that maintains an arbitrary angle between the movable part and the fixed part. The one touch opening function is one that automatically opens the movable part when a push button on the fixed part is pressed. The oil damper is such a damper as stores oil in a hinge part's case, and uses oil's viscosity to absorb vibrations when the movable part opens.
However, these conventional portable phones do not provide a satisfactorily user-friendly, safe, and small hinge mechanism.